Watching cataracts develop with an early detection technique

BETHESDA, Md. – Cataracts typically are diagnosed after they have progressed to the point of obscuring a patient’s vision, hindering daily routines. This is the most common cause of blindness and is especially prevalent in developing countries where complications after surgery are more common. The disease can be caused or exacerbated by many things, including age, smoking and uncontrolled diabetes, but there had been no way to predict or prevent their development – until now.

A cataract can be seen behind the pupil of this eye. Images courtesy of Dr. Manuel B. Datiles.
Researchers at the National Eye Institute and at NASA in Cleveland have collaborated to create a simple, noninvasive eye test to measure a protein that is related to cataract formation. The early detection of changes in this protein could give people enough warning to make lifestyle changes that would delay or prevent the development of cataracts.

The device used in the test is based on a laser technique called dynamic light scattering. Initially developed to measure the growth of crystals in zero-gravity environments, it can detect and analyze the amount of alpha-crystallin in the human eye. This protein binds to other, damaged proteins in the eye, preventing them from congregating and becoming cataracts, but α-crystallin deteriorates over time or because of adverse conditions. The less of the protein that is in your eyes, the more likely cataract formation becomes.

Dr. Manuel B. Datiles examines a patient’s eyes with the dynamic light-scattering device.
The scientists attached the probe – about the size of a short pencil – to one of their systems. Tested in animal models and in patients with varying grades of cataracts, it was found to detect changes in the amount of α-crystallin, even when the lens of the eye is still clear. The group currently is looking for funding to further research and development of the device and is performing studies in patients who are at higher risk for developing cataracts.

The scientists’ technique also may have applications beyond cataract research. Dr. Manuel B. Datiles of the National Eye Institute said that amyloids, the proteins that cause Alzheimer’s, are deposited in the lens of the eye as well as in the brain. With more research, it is possible that this probe could give an early warning of the development of Alzheimer’s, enabling early intervention.